[ECO code C80]
(The) Side Variation
White's QB loses more than a tempo taking the QB6(c6) knight here. It gives Black a Berlin Rosenthal with a move in hand, and advantage. W-Alt.
White Black White Black 1. P-K4 P-K4 6. BxKt?? 2. Kt-KB3 Kt-QB3 3. B-Kt5 P-QR3 4. B-R4 Kt-B3 5. 0-0 KtxP
Example ends: Undo or Jump or Clear